1. Field of the Invention
The invention relates to a semiconductor device and method for manufacturing the same, more particularly to a semiconductor device that can be produced at a relatively low manufacturing cost and with a relatively high production yield.
2. Description of the Related Art
Referring to FIGS. 1 and 2, a conventional semiconductor device 1 is shown to comprise a semiconductor chip 10, a dielectric tape layer 2 and a printed circuit board 3.
The semiconductor chip 10 has a pad mounting surface 12 with a plurality of bonding pads 11 provided thereon. The dielectric tape layer 2 has an adhesive surface 21 adhered onto the pad mounting surface 12 of the semiconductor chip 10, and a plurality of holes 20 that are registered with the bonding pads 11 to expose the latter. The dielectric tape layer 2 further has a wire mounting surface 22 opposite to the adhesive surface 21. A plurality of wires 23 that traverse the holes 20 are disposed on the wire mounting surface 22. A wire-bonding machine (not shown) processes the portions of the wires 23 that traverse the holes 20 (in the direction of the arrows shown in FIG. 1) so as to bond the wires 23 to the bonding pads 11 in the holes 20. Solder balls 24 are subsequently formed on the wires 23. The printed circuit board 3 has a circuit layout surface 30 formed with circuit traces 31 that bond with the solder balls 24 to establish electrical connection between the circuit traces 31 and the bonding pads 11 via the solder balls 24 and the wires 23.
Some of the drawbacks of the conventional semiconductor device 1 are as follows:
1. An expensive wire-bonding machine is needed to establish connection between the wires 23 and the bonding pads 11, thereby increasing the production costs. Also, defective products are produced during the wire-bonding operation due to inadequacies of the latter. Particularly, defective products are formed when wires break during the wire-bonding operation, thereby reducing the production yield.
2. The wires 23 are susceptible to oxidation and corrosion because they are exposed to air, thereby affecting reliability of the semiconductor device 1.
3. Solder balls 24 are needed to establish connection between the circuit traces 31 on the printed circuit board 3 and the semiconductor chip 10. The solder balls 24 are liable to drop off or form unstable electrical contacts, thereby affecting adversely the production yield.
4. Because solder balls 24 are used to connect the printed circuit board 3 and the semiconductor chip 10, the contact area between the printed circuit board 3 and the semiconductor chip 10 is relatively small and can lead to eventual undesired separation between the printed circuit board 3 and the semiconductor chip 10.
Therefore, the main object of the present invention is to provide a semiconductor device and a method for manufacturing a semiconductor device capable of overcoming the aforesaid drawbacks that are associated with the prior art.
According to one aspect of the present invention, a semiconductor device comprises:
a semiconductor chip having a pad mounting surface with a plurality of bonding pads provided thereon;
a dielectric tape layer having opposite first and second adhesive surfaces, the first adhesive surface being adhered onto the pad mounting surface of the semiconductor chip, the dielectric tape layer being formed with a plurality of holes at positions registered with the bonding pads to expose the bonding pads, each of the holes being confined by a wall that cooperates with a registered one of the bonding pads to form a contact receiving space;
a plurality of conductive contacts placed in the contact receiving spaces, respectively; and
a printed circuit board having a circuit layout surface adhered onto the second adhesive surface of the dielectric tape layer, the circuit layout surface being formed with circuit traces that are bonded to the conductive contacts to establish electrical connection with the bonding pads.
According to another aspect of the present invention, a method for manufacturing a semiconductor device comprises:
adhering a first adhesive surface of a dielectric tape layer onto a pad mounting surface of a semiconductor chip, the dielectric tape layer being formed with a plurality of holes at positions registered with bonding pads provided on the pad mounting surface to expose the bonding pads, each of the holes being confined by a wall that cooperates with a registered one of the bonding pads to form a contact receiving space;
placing a plurality of conductive contacts in the contact receiving spaces, respectively; and
adhering a circuit layout surface of a printed circuit board onto a second adhesive surface of the dielectric tape layer opposite to the first adhesive surface, and bonding circuit traces formed on the circuit layout surface to the conductive contacts to establish electrical connection with the bonding pads.
Preferably, the second adhesive surface is provided with a heat-curable adhesive having a curing point that is lower than melting point of the conductive contacts. Thus, adhering of the printed circuit board onto the dielectric tape layer and bonding of the circuit traces to the conductive contacts can be performed simultaneously via a heat curing operation such that the circuit layout surface is already adhered onto the second adhesive layer prior to melting of the conductive contacts.